feat(backend): 添加光标支持

CMakeLists.txt

@@ -26,6 +26,7 @@ project(${APP_NAME}
 add_executable(${APP_NAME}
     ${SOURCE_DIR}/backend/output_utils.c
     ${SOURCE_DIR}/backend/x11/backend.c
+    ${SOURCE_DIR}/backend/x11/cursor.c
     ${SOURCE_DIR}/backend/x11/event.c
     ${SOURCE_DIR}/backend/x11/window.c
 
@@ -76,6 +77,7 @@ find_package(PkgConfig REQUIRED)
 pkg_check_modules(deps REQUIRED
     xcb
     xcb-aux
+    xcb-cursor
     xcb-icccm
     xcb-keysyms
     xcb-randr

src/backend/x11/backend.c

@@ -18,6 +18,7 @@
 #include <xcb/xproto.h>
 
 #include "backend/output_utils.h"
+#include "backend/x11/cursor.h"
 #include "backend/x11/window.h"
 #include "base/app.h"
 #include "base/array.h"
@@ -184,10 +185,13 @@ backend_t *backend_create(const char *display_name) {
 
   backend->key_symbols = xcb_key_symbols_alloc(conn);
 
+  cursor_init(backend);
   atoms_init(backend);
   create_wm_check_window(backend);
   create_no_focus_window(backend);
 
+  window_change_cursor(backend, root, ZDWM_CURSOR_NORMAL);
+
   return backend;
 }
 
@@ -204,6 +208,8 @@ void backend_destroy(backend_t *backend) {
   xcb_key_symbols_free(backend->key_symbols);
   backend->key_symbols = nullptr;
 
+  cursor_cleanup(backend);
+
   xcb_disconnect(backend->conn);
   backend->conn = nullptr;
   free(backend);

src/backend/x11/cursor.c

@@ -0,0 +1,51 @@
+#include <stddef.h>
+#include <xcb/xcb_cursor.h>
+#include <xcb/xproto.h>
+
+#include "base/macros.h"
+#include "base/memory.h"
+#include "internal.h"
+
+static const char *const cursor_name_map[] = {
+  [ZDWM_CURSOR_NORMAL] = "left_ptr",
+  [ZDWM_CURSOR_MOVE]   = "fleur",
+  [ZDWM_CURSOR_RESIZE] = "bottom_right_corner",
+};
+
+static xcb_cursor_context_t *get_xcb_cursor_context(backend_t *backend) {
+  if (backend->cursor_context) return backend->cursor_context;
+
+  auto conn   = backend->conn;
+  auto screen = backend->screen;
+  if (xcb_cursor_context_new(conn, screen, &backend->cursor_context) == 0) {
+    return backend->cursor_context;
+  }
+
+  return nullptr;
+}
+
+void cursor_init(backend_t *backend) {
+  auto ctx = get_xcb_cursor_context(backend);
+  if (!ctx) return;
+
+  for (size_t i = 0; i < countof(backend->cursors); ++i) {
+    auto cursor_name    = cursor_name_map[i];
+    backend->cursors[i] = xcb_cursor_load_cursor(ctx, cursor_name);
+  }
+}
+
+void cursor_cleanup(backend_t *backend) {
+  constexpr size_t count = countof(backend->cursors);
+  for (size_t i = 0; i < count; ++i) {
+    xcb_free_cursor(backend->conn, backend->cursors[i]);
+  }
+  p_clear(backend->cursors, count);
+  xcb_cursor_context_free(backend->cursor_context);
+  backend->cursor_context = nullptr;
+}
+
+xcb_cursor_t cursor_get_xcb_cursor(backend_t *backend, cursor_t cursor) {
+  if (backend->cursor_context == nullptr) return XCB_CURSOR_NONE;
+
+  return backend->cursors[cursor];
+}

src/backend/x11/cursor.h

@@ -0,0 +1,9 @@
+#pragma once
+
+#include <xcb/xproto.h>
+
+#include "internal.h"
+
+void cursor_init(backend_t *backend);
+void cursor_cleanup(backend_t *backend);
+xcb_cursor_t cursor_get_xcb_cursor(backend_t *backend, cursor_t cursor);

src/backend/x11/internal.h

@@ -3,6 +3,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <xcb/xcb.h>
+#include <xcb/xcb_cursor.h>
 #include <xcb/xcb_keysyms.h>
 #include <xcb/xproto.h>
 
@@ -78,7 +79,14 @@ typedef struct window_configure_list_t {
   size_t capacity;
 } window_configure_list_t;
 
-struct backend_t {
+typedef enum cursor_t {
+  ZDWM_CURSOR_NORMAL,
+  ZDWM_CURSOR_MOVE,
+  ZDWM_CURSOR_RESIZE,
+  ZDWM_CURSOR_COUNT,
+} cursor_t;
+
+typedef struct backend_t {
   xcb_key_symbols_t *key_symbols;
   xcb_connection_t *conn;
   xcb_screen_t *screen;
@@ -94,11 +102,14 @@ struct backend_t {
   xcb_window_t focus_window;
   bool update_focus;
 
+  xcb_cursor_t cursors[ZDWM_CURSOR_COUNT];
+  xcb_cursor_context_t *cursor_context;
+
   window_configure_list_t config_list;
   window_list_t unmap;
   window_list_t map;
   window_list_t kill;
-};
+} backend_t;
 
 bool populate_window_event(
   struct backend_t *backend,

src/backend/x11/window.c

@@ -3,10 +3,12 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <xcb/xcb.h>
+#include <xcb/xcb_aux.h>
 #include <xcb/xcb_icccm.h>
 #include <xcb/xcb_keysyms.h>
 #include <xcb/xproto.h>
 
+#include "backend/x11/cursor.h"
 #include "base/macros.h"
 #include "base/memory.h"
 #include "core/backend.h"
@@ -451,3 +453,13 @@ visual_t *window_get_visual(backend_t *backend, bool prefer_alpha) {
 
   return visual;
 }
+
+void window_change_cursor(
+  backend_t *backend,
+  xcb_window_t window,
+  cursor_t cursor
+) {
+  auto conn              = backend->conn;
+  xcb_params_cw_t params = {.cursor = cursor_get_xcb_cursor(backend, cursor)};
+  xcb_aux_change_window_attributes(conn, window, XCB_CW_CURSOR, &params);
+}

src/backend/x11/window.h

@@ -118,3 +118,9 @@ typedef struct visual_t {
  * @returns 返回的信息使用后记得使用 free 释放
  */
 visual_t *window_get_visual(backend_t *backend, bool prefer_alpha);
+
+void window_change_cursor(
+  backend_t *backend,
+  xcb_window_t window,
+  cursor_t cursor
+);